<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>扩展选择器</title>
    <style>
           div p
           {
               color:red;
           }
           div>p
           {
               border:1px solid;
           }
         input[type="text"]
         {
             border:5px solid;
         }
         a:link
         {
             color:pink;
         }
           a:active
           {
               color:yellow;
           }
           a:hover
           {
               color:green;
           }
           a:visited
           {
               color:red;
           }

    </style>
</head>
<body>
     <div>
         <p>传智播客</p>
     </div>
     <p>黑马程序员</p>
      <div>aaa</div>
        <input type="text"><br>
     <input type="password"><br>
     <a href="#">传智播客</a>
</body>

</html>